Method of and apparatus for producing the reversal of regenerative furnaces



March 18 1924 G. H. lSLEY METHOD OF AND APPARATUS FOR PRODUCING THEREVERSAL 0F REGENERATIVE FURNACES Filed March 31. 1920 Patented 192d,

'UMTEZQ stares earner; easier...

GEORGE H. ISLEY, 0F WORCESTER, MASSACHUSETTS, ASSIGNOR T0 MOBCTAN CON-STRUGTION COMPANY, MASSACHUSETTS.

METHOD OF AND APFARATUS FOR PRODUCING THE REVER'SAL OF REGENEBATIVE OFWORCESTER, MASSACHUSETTS, A CORPORATION OF FURNACES.

Application filed March 31, 1920. Serial No. 370,186.

To all whom it may concern:

Be it known that I, Gnonen H. IsLEY, a citizen of the United States,residing at -ll orcester, in the county of Worcester and Commonwealth ofMassachusetts, have invented a new and useful Improvement in a Method ofand Apparatus for Procuring the Reversal of Regenerative Furnaces, ofwhich the following, together with the accompanying drawings, is aspecification.

The. present invention relates to certain improvements connected withthe act of reversing a regenerative furnace, in order to change, whendesired, the direction of flow of the air and gas through the passagesof said furnace.

The improvements reside in a novel method of procuring the reversal, aswell as in the construction and arrangement of the reversinginstrumentalities. The objects of the invention are to obtain greatersimplicity in the construction of devices of this class, and to providefor the effective combustion of all gases that are trapped or otherwiseconfined, when the reversal of the furnace is inaugurated; a furtherobject is to provide improved means for controlling the flow of air tothe furnace with the use of a specially constructed damper or valvedisposed between the furnace and the stack.

The several features of the invention will be fully pointed out indetail hereinafter, reference being had to the accompanying drawings,wherein Figure 1 is a diagrammatic view illustrating the application ofthe invention to a regenerative furnace of well known construction.

Figure 2 is a longitudinal sectional view on the line 2 2, Fig. l, ofthe reversing device that is provided at each end of the arrangementshown in Fig. 1.

Figure 8 is a sectional view, on an enlarged scale, taken on the line33, of Fig. 1, and showing the detailed construction of one form of aircontrolling device. 7

Figure 4: is a sectional view showing a modified form of air controllingdevice.

Figure 5 is a diagrammatic view, illustrating a somewhat differentarrangement of reversing apparatus from the arrangement shown in Fig. 1.

Like reference characters refer to like parts in the different figures.

In the form of the invention illustrated in Fig. 1, the regenerativefurnace 1, of any ordinary type, is provided with the usual gasregenerator passages 2, 2, and the usual air regenerator passages 3, 3,At each end of the furnace are provided reversing devices 4:, 1,respectively, each of which is of the form shown in Fig. 2, consistingof a single shiftable hood 5, that cooperates with the terminals ofthree adjacent alined flues 6, 7 and 8. These terminals are completelysurrounded by a body of water contained in a water seal pan or casing 9.'Each' hood 5 is of suflicient length to cover and water seal, by meansof its depending apron 10, two of the three adjacent terminals of lines6, 7 and 8, and each hood 5 is so pivoted to its pan 9, by means oflinks 11, 11, as to be capable of being shiftedbodily, by a parallelmotion, into its other position, where it covers and seals theremainingflue terminal, at the same time exposingthe one at the opposite endwhich it had previously sealed.

At each end of the furnace, the fine 6 is in communication with a sourceof gas supply 12, usually connected with a gas producer, not shown. Eachflue 7 communicates directly with the adjacent gas regenen ator passage2 or 2 of the furnace. Each fine 8 communicates with a conduit orpassage 13 that at one end connects with the adjacent airregeneratorpassage 3 or 3, and at the other end joins with a common stack passage14.

The two reversing devices 4, a, do not differ in constructionessentially from the gas reversing devices shown and described in myUnited States Letters Patent No. 1,408,946, dated March 7, 1922.Associated with each of said reversing devices 1-, 1 are swinginggravity closing covers 15, 15, one for the terminal of gas supply flueG, and the other for the terminal of flue 8 that has a connectiontopassage 13. As described in my aforesaid copending application, eachcover 15 is pivoted on a rod 16 that extends 'transversely of the waterpan 9, and each cover adjacent its pivotal axis has an out wardlyprojecting ear or lip 17 adapted to be engaged by the depending skirt orapron,

10 of the hood 5. In this way, each cover 15 is tipped up into openposition, immediately following the descent of the hood 5 into positionfor sealing the flue terminal with which said cover is associated; andwhen the hood 5 is moved to its other position, uncovering said flueterminal, the associated cover 15 descends by gravity and seals theterminal before the seal made by the apron 10 is broken.

In each passage Or conduit 13, between the stack connect-ion 1a and theterminal 8 is disposed a sliding damper 18, Fig. 3, which when lowered,in the position shown, is adapted to close off coinmunca'tron with saidstack connection. Said damper 18 is made hollow to provide an interiorpassage 19 therethrough, which opens at its lower end at 20, on the sideleading to the furmice. The operation of the damper 18 may be effectedin any suitable manner, as by means of a rod 21, which passes through asuitable housing 22 erected on the conduit or passage 13, said rodserving to raise or lower the damper, as desired. The housing 22provides an opening to the atmosphere, said opening being controlled bya swinging gate 24 that has a suitable connection 25 with the rod 21.When the damper 18 is in the position illustrated in Fig. 3, itcompletely shuts off communication with the stack connection ll, and atthe same time, the gate 2fbeing open, air enters the housing 22therethrough and is drawn through the passage 19 of the damper to thefurnace, by way of passage or conduit 13. In this way the air supply tothe furnace is made available to keep the damper 0001, thus preventingthe frequent burning out of same which would otherwise occur, due to itsproximity to the stack connection 1 1. hen the damper 18 is raised, thecommunication of passage 13 with the stack connection let is restoredand at the same time the gate 2 f is closed, due to its connection withthe rod 21.

Referring to Fig. 1, when the two hoods 5, 5, are disposed in thepositions indicated, that is, at their extreme left hand positions,burning gaseous fuel will pass through the furnace in the directionindicated by the arrows. That is to say, the gas from the producer orother source enters the, furnace from the left hand side, by way ofsupply lines 12 and 6, hood 5 of reversing device 1, flue 7, and gasregenerator passage 2; the exposed terminal of adjacent flue 8 underthese conditions being sealed by its cover 15. The air enters the lefthand passage or conduit 13 through the hollow damper 18 which underthese conditions is in its closed position, as shown in Fig. 3, andcompletely shuts off the left hand passage 13 from the stack connection1 1. This air passes into the furnace by way of regenerator passage 3,and is prevented from escaping past the exposed terminal of flue 8because, as before stated, the cover 15 seals said terminal,

Leaving the furnace at the right hand side thereof, the products ofcombustion on their way to the right hand passage or conduit 13 andstack connection 14 pass in part directly into passage 13 from airregenerator passage 3, and in part through gas regenerator assage 2,flue 7, hood 5 of reversing device 4, and flue 8, the terminal of thelatter being open because its cover 15 is held in raised position by thehood 5. Under these conditions the right hand damper 18 is maintained inraised or open po-sition,thus communicating the right hand passage 13with the stack connection 1%. Also, as will be clear, the exposed gassupply fine 6 at the right hand side of the furnace, is com pletelysealed at this time by its associated cover 15.

When it is desired to reverse the flow of gases through the passages ofthefurnace the following preferred method of operation may be adopted:The hood 5 of the left hand reversing device 4 is first moved into itsother position, thereby causing the cover 15 of fine 6 to shut off thesupply of gas, said hood at the same time opening the other cover 15,and connecting the flues 7 and 8. lVith no other change in the relativeposition of the parts, the furnace is allowed to operate for a shorttime under these conditions, and it will be clear that during thisperiod of operation the direction of gaseous flow through the furnaceremains unchanged, since the stack draft is exerted through the righthand regenerator passages 2 and 3. With the aid of this draft,supplemented by the high temperatures prevailing in the regeneratorpassages, all the fresh gas between reversing device 4.- and the furnaceis drawn inwardly, said gas being displaced by an inwardly drawn volumeof cold air, namely a part of the air that enters through left handhollow damper 18 and passes to the furnace through conduit 13. Theentrance of this air by way of flue 8, hood 5, and flue 7, in the wakeof fresh gas, absolutely insures that all gas remaining in the left handpassages shall be burned. After allowing a suitable time for thecombustion of all such trapped fresh gases, the hood 5 of righthandreversing device 41- is shifted, and simultaneously therewith thedampers 18, 18, have their positions reversed, the left hand damperbeing raised and the right hand damper lowered. When this is done, thereversal of the furnace is completed, the gas and air entering at theright hand side. and the burned gases leaving at the left hand side, andpassing to stack connection 14 by way of left hand passage 13. Becauseof the combustion of the trapped gas, carried into the furnace by theair that enters passage 2, all danger of the explosions that frequentlyoccur when reversing a furnace, is eliminated. In lieu of the mode ofoperation above pointed out, it is obvious that the furnace can bereversed in the usual Way, if desired, by operating the hoods 5, 5, anddampers 18, 18. simultaneously.

The parallel motion of which the hoods 5, 5, partake may be impartedthereto in any suitable manner; the force required to impart the initialupward componentof the motion is supplied in part by the gravitationaltendency ofthe open cover 15, and may be augmented by the use ofcounterweights, not shown. To control the volume of gas entering thefurnace, the degree of opening of the covers 15 of gas flue 6 may beregulated by an adjustable stop 26, to limit the descent of skirt 10.Such of the covers 15 as are subject to hot exhaust gases from thefurnace may be provided with pipes 27 for circulating cooling Water, andall of said covers 15, as pointed out in my aforesaid copendingapplication are readily removable for replacement or repair.

A modification of the air controlling mechanism is illustrated in Fig.4, where, instead of separate dampers 18, 18, for the two passages 13, asingleswinging valve or damper 28 is provided. Said single damper 28 ismade hollow for the passage of air, the

same as the two dampers 18, and the air en- 2 ters through a suitablehollow extension or stem 29. The damper structure is pivoted at 30,andin one position, as shown in Fig.

4, cuts off communication between stack connection 14 and the left handpassage 13, at the same time opening said left hand passage 13 to theatmosphere. In the other po sition the damper 28 performs the samefunctions with respect to the right hand passage 13, but permitscommunication of left hand passage 13 with the stack connection 14. v

A modification-inthe construction and arrangement of the apparatusemployed for securing the improved method of reversing the furnace, asdescribed above, is shown in Fig. 5. In this figure the same arrangementof reversing device 4 and 4 is shown,

' but the'opposite passages or conduits 13 here areprovided with openterminals 31, 31, disposed in. alinement and having interposed betweenthem the open terminal of a stack flue 32. A reversing device 33,similar in all respects to the shiftable hoods 5 is made operative overthe terminals of the flues 31, 31, and 32; at its ends the hood ofdevice 33 carries pivoted adjustable extensions 34, 34, for cooperation,when needed, with the exposed terminals 31, to control the amount of airentering the same. In the position of parts shown in Fig. 5, the flow ofgaseous products through the furnace is from left to right, in thedirection of the arrows, the two reversby the gas being filled with coolair drawn in through passage 13 and hood 5. Thereupon the devices 4 and33 are shifted, the former to the right and the latter to the left, witha consequent immediate reversal in the flow ofgases through the furnace.Obviously, as

in the first described form of the invention,

the reversal may, if desired, be accomplished by moving all thereversing devices simul taneously, but when this is done, there isinvariably some wastage of the fresh gas that is'trapped in theregenerator passages 2, 2? of the furnace.

I claim,

1. The herein described method of reversing a regenerative furnace,which consists in discontinuing the gas supply to one gas regeneratorpassage while simultaneously con necting said gas regenerator passage tothe associated air regenerator passage on the same side of the furnace,and afterwards connecting both of said regenerator passages to thestack, simultaneously with the. connection ofthe opposite gas and airregenerator passages to the gas and air supply.

2. The herein described method of reversing a regenerative furnace,which consists in cutting oil the gas supply to one side of the furnacein advance of actual reversal, and causing a part of the air normallysupplied to said side to be diverted into the adjacent gas regeneratorpassage.

' The herein described method of resists in disconnecting the gasregenerator passage on one side of the furnace from the;

source of gas supply, connecting said passage with the air regeneratorpassage on the same side of the furnace, and afterwards opening saidside of the furnace to the stack, simultaneously with the connection ofthe other side of the furnace to gas and air supply. I 4. The hereindescribed method of reversing a regenerative furnace, which consists inallowing an interval to elapse between the act of shutting off thesupply of gas to one gas regenerator passage and the act ofdisconnecting the opposite air and gas regenerator passages from thestack, and in said interval providing a connection betweensaid firstmentioned gas regenerator passage and its associated air regeneratorpassage on the same side of the furnace.

5. The combination with the air and gas In advance of the actualreversal of Under these s condi fines atone end of a regenerativefurnace, of reversing means for said furnace, adapted in one position toprocure connection of both of said fines, to a single source of airsupply.

'6. The combination with the air and gas flues at one end of aregenerative furnace, of a single air supply conduit at said end, andreversing means for said furnace adapted in one position to connect bothof said flues with said air supply conduit.

7. The combination with the air and gas fines at each end of aregenerative furnace, of a stack flue connectedwith each air flue, meansfor admitting air to one of said stack flues when the other is connectedto the stack, and reversing means for the furnace adapted in oneposition to connect the said fine to which air is admitted to the gasfine at the same end of the furnace.

8. The combination with a discharge conduit or passage, of a shut-offdevice therefor, adapted, when closed, to admit air to said conduit orpassage, for flow in the opposite direction to said discharge.

9 The combination with a, stack flue of a furnace, of a damper adaptedin one position to shut off the furnace from the stack, and in saidposition to provide a. passage there-through for the entrance of air tothe furnace.

10. In apparatus of the class described, a passage connecting a furnacewith a stack, and a damper for closing said passage, adapted, whenclosed, to connect said furnace through said passage with theatmosphere.

11. In apparatus of the class described, a passage connecting a furnacewith a stack, and a damper for closing said passage, and providing, whenclosed, a conduit for the flow of air to said furnace.

12. In apparatus of the class described, a passage for the flow ofburned gases from a furnace to a stack, and a damper for closing saidpassage, said damper being cooled by a current of air therethroughflowing to said furnace.

13. In apparatus of the class described, a pair of passages leading froma furnace to a stack, and means operable to shutoff one of said passagesfrom the stack, and to cause a flow of air therethrough to the furnace.

14. In apparatus of the class described, a damper for shutting offcommunication, between afurnace and a stack, said damper having apassage therethrough for connecting said furnace with the atmosphere.

15. In apparatus of the 'class described, the combination with the stackflue of a furnace, of a damper operable in said fine and providing, whenclosed, a passage for the entrance of air to said furnace, and meansoperable by the movement of said damper into open posit-ion forpreventing the flow of air through said passage.

16. The combination with a regenerative furnace having adjacent air andgas flue terminals at each end, a movable reversing device at each end,operable to connect the gas flue terminal either with the source of gassupply or with the air flue terminal, a.

stack passage at each end connnunicating with the air flue terminal, andmeans for supplying air to the furnace through one or the other of saidstack passages.

17. The combination, with each set of air and gas passages of aregenerative furnace, of a reversing device adapted in one position todiscontinue the'gas supply, said reversing device, in said position,providing a connection between the gas passage and the air supply. 1

18. The combination, with each set of air and gas passages of aregenerative furnace, of a reversing device adapted, by actuation inadvance of actual reversal of the furnace, to connect adjacent gas andair passages.

19. The combination, with a regenerative furnace, of duplicate reversingdevices therefor, adapted to procure a reversal in the flow of gaseousproducts through the furnace, one of said devices, when actuate-d inadvance of the other, procuring disconnection of the gas supply, andsinniltaneously, the passage through itself of air, in the wake of thetrapped gas;

20. The combination with a' regenerative furnace, of air and gaspassages at each end thereof having adjacent terminals, a gas supplypassage at each end of the furnace with its terminal adjacent that ofthe gas passage, gravity actuated closures for the terminals of said gassupply and air passages, and a shiftable reversing hood'in operativerelation to said terminals and adapted to mmal.

' GEORGE I-I. ISLEY.

